1. Field of the Invention
The present invention relates to a microwave shielding device for use in a microwave oven and more particularly, to a microwave leakage shielding device for use in a door of a microwave oven for improving the wave shielding capability thereof so that the microwave oven is refined in appearance and the microwave shielding device is easy in assembling.
2. Description of the Prior Art
Generally, the conventional microwave shielding devices include two types such as a slit installing type as shown in FIG. 2 and a seal plate-slit combination type as shown in FIG. 3.
As shown in FIG. 2, the conventional shielding device includes an installing slit 5 provided in a door frame 3 in order to form a choke seal and dual metals formed by coupling a seal plate 4 with a flange 1 which is peripheral edge of the entrance opening of the heat chamber thereby forming a structure for shielding the leaking waves. Furthermore, the slit installing type includes a first choke seal and a second choke seal in addition to the dual metals. Thus a first microwave leakage shielding effect is obtained by the coupling of the dual metals and a second microwave leakage damping effect is obtained through the first choke seal and the second choke seal.
As shown in FIG. 3, the conventional shielding device includes the seal plate 4 integrally formed with a slit 4, of the seal plate 4 for serving as a tuning post member through the combination of the slit 4,, the choke seal, and the dual metals. Thus a first microwave leakage damping effect is obtained through the slit 4,, a second microwave leakage damping effect is obtained through the formation of the choke seal, and a third microwave leakage damping effect is obtained through the coupled metals thereby forming a triple shielding structure.
However, in the device of FIG. 2, a space has to be formed within the door frame 3 since the installing slit 5 has to be formed within the door frame 3. Therefore, the size of the door frame has to expand and if the installing slit 5 is not provided at the proper position in the door frame 3, the leakage damping cannot be obtained.
Furthermore, in the device of FIG. 3, it is very difficult to install the choke cover and when the door is opened, the choke cover is too much exposed to the outside thereof thereby aggravating the aesthetic appearance of the microwave oven.